Health care represents the largest industry in the United States, current estimates place it at approximately 16% of the gross domestic product, and increasing. Technological innovations over the last half century have aided the growth of the health care industry. Health care systems engineering is a particular catalytic area of development within the health care industry. Industrial and systems engineers along with operations researchers are making significant advances in the application of health care delivery optimization approaches. One specific and promising subset of health care delivery includes cancer treatment planning, specifically radiation treatment planning (RTP) for the treatment of cancer.
Radiotherapy treatment planning has been revolutionized through the use of CT and MRI scanners, which provide three-dimensional delineation of tumors and adjacent healthy tissues. Tumor treatment simulation techniques have enhanced the accuracy of radiotherapy treatment. 3D Conformal Radiotherapy (3DCRT) enables the radiation beam to be shaped to fit the target profile from a beam's eye view (BEV). A variable number of beams is often used for 3DCRT. Higher effective doses of radiation can therefore be delivered to the target tissue, while limiting the exposure to healthy tissue adjacent to the target. 3DCRT techniques have undergone technological advancement to provide advanced high precision radiation. Intensity-Modulated Radiation Therapy (IMRT) is often considered the next generation of 3DCRT, providing targeted radiation delivery to tumors by controlling or modulating the radiation beam's intensity. IMRT often allows for a higher dose of radiation as compared to previously known methods. However, IMRT is a complex technology for radiation treatment, which often involves the use of a multileaf collimator to shape the beam and makes it possible to control, or modulate, the amount of radiation that is delivered from each of the delivery directions relative to the patient. Due to the complexity there are numerous treatment planning problems, which include radiation dose optimization and beam angle selection.
Current commercial treatment planning systems for radiation therapy often require the user to employ expert judgment to determine the beam angles that are required to use those systems. An expert's judgment is often subject to interpretation and a host of variables that may lead to inaccurate results. It would be advantageous for a treatment planning system for radiation therapy to generate beam sets that demonstrate significant improvements relative to beam sets that are obtained through expert judgment. It would be further advantageous to couple beam angle optimization with dose optimization. It would be a further advantage to automate the coupling of beam angle optimization and dose optimization for RTP.